EP0433798A2 - Device for exchanging a printing plate - Google Patents

Abstract

In a method and a device for carrying out the method for automatically loading and unloading a printing plate in or from a plate cylinder of a rotational printing machine, a printing plate loading and unloading device with transport rollers is provided, in which the printing plate is placed.

Description

The invention relates to a method and a device for carrying out the method for automatically feeding a printing plate to and discharging a plate cylinder of a rotary printing press.

Through the EP note. 02 68 857 a semi-automatic device is known with which it is possible to attach a printing plate on the plate cylinder of a rotary printing press.

A disadvantage of the device according to EP application. 02 68 857 is that the pressure plate must be inserted into the clamping device by hand; In addition, the commands for placing the pressure plate, clamping and clamping must be entered manually on a control panel.

The invention has for its object to provide a method for feeding and discharging a printing plate to and from a plate cylinder and a device for performing the method.

The object is achieved by the features of the characterizing parts of claims 1, 2 and 4.

The advantage of the method and the device according to the invention is, in particular, that for attaching the printing plates to the plate cylinder Auxiliary staff can be used. Touching the personnel with the rotating parts of the machine is excluded, ie safety is increased. Machine downtimes for changing the printing plates are reduced.

A position relevant to the plate on the plate cylinder becomes more precise. A waste of paper waste caused by lengthy registration correction is reduced.

Fig. 1

eine Seitenansicht der erfindungsgemäßen Druckplattenzuführ- bzw. -abführvorrichtung im Schnitt, Druckplattenzuführstellung,

Fig. 2

wie Fig. 1, jedoch andere Winkelstellung des Plattenzylinders, Druckplattenlösestellung,

Fig. 3

eine vergrößerte Seitenansicht der Klemmeinrichtung für ein Druckplattenende, Druckplattenklemmstellung,

Fig. 4

eine vergrößerte Seitenansicht der Klemmeinrichtung für einen Druckplattenanfang,

Fig. 5

Steuereinrichtung und Steuerrechner,

Fig. 6

einen Ablaufplan für das Zuführen einer Druckplatte zum Plattenzylinder,

Fig. 7

einen Ablaufplan für das Abführen einer Druckplatte vom Plattenzylinder.

An embodiment of the invention is shown in the drawings and is described below. Show it

Fig. 1

a side view of the printing plate feed or discharge device according to the invention in section, printing plate feed position,

Fig. 2

like Fig. 1, but different angular position of the plate cylinder, printing plate release position,

Fig. 3

an enlarged side view of the clamping device for a printing plate end, printing plate clamping position,

Fig. 4

an enlarged side view of the clamping device for a printing plate start,

Fig. 5

Control device and control computer,

Fig. 6

a flow chart for feeding a printing plate to the plate cylinder,

Fig. 7

a flow chart for the removal of a printing plate from the plate cylinder.

A rotary printing press has several printing units 1 (e.g. 4), each of which, among other things. a plate cylinder 3, a blanket cylinder 4 and an impression cylinder 6 included. These are stored in the usual way in side frames of the rotary printing press.

Since the various printing units 1 are almost identical to one another, the invention is only described with reference to a printing unit 1.

A printing plate feed or removal device 9 is provided on an access side 8 to the cylinders 3, 4, 6 of the printing unit 1. This is attached to a cover plate 11, which together with the pressure plate feed or discharge device 9 by means of two rockers (arms) 17; 18, which are fastened to the side frames of the printing towers 1, are arranged pivotably in two end positions. The swivel radius is shown by dashed lines. For this purpose, an upper and lower joint 14; 16 provided, in each of which a first end of the rockers 17; 18 is pivotally mounted. A second end of the rockers 17, 18 is pivotally mounted on the side frames. The cover plate 11 as a coupling, the wings 17, 18 and the frame of the printing unit 1 as a web thus form a four-bar link.

A working cylinder 19 is pivotally mounted on a lower end on both sides of the cover plate 11. A piston rod 21 of the working cylinder 19 is articulated to a lever 22. In its end, the lever 22 rotatably supports a continuous pressure roller 26 arranged parallel to the axis of the plate cylinder 3. The pressure roller 26 can also be offset. The pressure roller 26 has a soft surface (e.g. rubber; plastic) in relation to a pressure plate 27. The lever 22 is pivotally mounted about an axis 30 of a drive roller 29 rotatably mounted in side supports (not shown) of the cover plate 11. The drive roller 29 is offset and has a drive (z. B. gear drive, electric motor, etc.).

In the exemplary embodiment, this is represented schematically by a chain wheel 31 with a drive chain 32.

The drive roller 29 and the pressure roller 26 are also in drive connection, wherein they preferably have the same peripheral speeds.

A pressure roller 33 can be brought into contact with a drive roller 29. For this purpose, the pressure roller 33 is rotatably mounted in a first end of a two-armed lever 34.

The lever 34 is pivotably mounted almost centrally in the side supports of the cover plate 11 and has a joint 36 at a second end, which is connected to one end of a piston rod 37. The piston rod 37 is part of a working cylinder 40 which is articulated to the cover plate 11.

The printing plate feed or discharge device 9 consists of an approximately printing plate-wide housing 38 with a storage chamber 39. When viewed in section, the housing 38 has a slight curvature such that an upper part of the housing 38 is aligned almost vertically and a lower part of the Housing 38 is oriented tangentially to a lower part of the plate cylinder 3. A funnel-shaped opening 41 in the upper part of the housing 38 facilitates the insertion of the pressure plate 27.

The housing 38 is made in two parts and has a hinge 42 above the cover plate 11, by means of which an upper part of the housing 38 can be folded down, whereby an upper part of the printing tower 1, in which an inking unit (not shown) in the usual manner Printing machine is provided, is accessible to an operator.

A front wall 43 of the housing 38 extends up to shortly before the pressure roller 26 and has openings 44 in the area of the drive roller 29, through which surface areas of the remote drive roller 29 protrude into the storage chamber 39. A rear wall 46 of the housing 38 extends shortly before the pressure roller 33. Behind the pressure roller 33, a plurality of ejection fingers 45 are provided parallel to the front wall 43, which are fixedly arranged on an ejection finger shaft 47 pivotably mounted in the side supports of the cover plate 11. A drive device for the ejection finger shaft 47 is shown in FIG. 2. At a distance from the pivotable mounting of the ejection finger shaft 47, a piston rod 48 articulates on a lever 50 of the ejection finger shaft 47. The piston rod 48 is part of a working cylinder 49, the is articulated to the cover plate 11. The ejection fingers 45 are pivoted by means of the piston rod 48 in such a way that their tips 68 can dip into the periphery 62 of the plate cylinder 3 or lift off over the periphery.

Means are also provided (not shown) which cause the ejection fingers 45 to be able to dip into the periphery 62 of the plate cylinder only in the area of the plate cylinder pit 2.

The plate cylinder 3 has a plate clamping and tensioning device 53, 54 in a pit 52. The plate clamp is e.g. known from DE-PS 36 26 936. This is particularly characterized by a conveniently arranged pivot pole of the clamping flap 55; 56 out. This has the effect that a pressure plate end 57 is not hindered by the clamping flap 55 when it is inserted into or removed from the plate clamping device 54.

The jig is e.g. known from DE-OS 36 04 071.

Upon rotation of the plate cylinder 3 from a pressure plate release position A clockwise (backward) and pressurization of the working cylinder 49, the tips 68 of the gripper fingers 45 pass through corresponding openings 64 in the clamping flap 55 into recesses 65 in the plate clamping and tensioning device 54 under the pressure plate end 57 and thus support a lifting of the pressure plate end 57 from a clamping support 63.

Provided actuating means for the plate clamping and tensioning device 53, 54 are supplied with working medium via a rotary entry on the plate cylinder journal. Of course, it is also possible to provide devices which, when the plate cylinder 3 is at a standstill in a plate cylinder position A, B, C, supply it with working medium via its end face or lateral surface. The actuating means can act hydraulically, pneumatically, mechanically or also electrically.

In printing operation, the printing plate feed or discharge device 9 is in a position according to FIGS. 1 and 2. In this position, access to the cylinders 3, 4, 6 is closed by the cover plate 11, but the pressure roller 26 is pivoted from the plate cylinder 3 (not shown). The cover plate 11 has a view (not shown) on the plate cylinder 3.

In a printing plate release or feed position A, B, the pressure roller 26 is set against the plate cylinder 3.

After the end of the current print job, the plate cylinder 3 moves into the predetermined angular position A (FIG. 2). The clamping flap 55 is opened. A pressure plate end 57 pivots outward due to its elastic inherent tension until it rests against a lower part of the front wall 43 or is lifted from the clamping support 63 by the ejection fingers 45 by rotating the plate cylinder 3 into the pressure plate clamping position C by the ejection fingers 45.

A rotation of the plate cylinder 3 in connection with the driven pressure roller 26 clockwise (backwards) now causes the printing plate 27 to be removed from the plate cylinder 3 or the printing plate 27 to be pushed into the storage chamber 39. The pressure plate end 57 thereby comes into a nip of the transport rollers (drive roller / Pressure roller) 29, 33, which grip the printing plate end 57 and transport the printing plate 27 further at the same or greater peripheral speed as the plate cylinder 3, when the clamping flap 56 of the plate clamping and tensioning device 53 for the printing plate start 58 in the plate cylinder angle position B (printing plate feed position) (FIG 1) or was opened shortly before. The pressure plate 27 is transported by the transport rollers 29, 33 until the pressure plate end 57 of the pressure plate 27 has left the nip, i.e. is transported out of the lower part of the printing plate feed or discharge device 9. An operator can now grasp the pressure plate end 57 and remove the pressure plate 27 from the storage chamber 39.

To equip the plate cylinder 3 with a new pressure plate 60, an operator places the new pressure plate 60 with the pressure plate start 58 in front into the storage chamber 39 until it rests on the transport rollers 29, 33. The plate cylinder 3 is in the printing plate feed position B (FIG. 1), and the clamping flap 56 is open. Now the transport rollers 29, 33 are activated and transport the new pressure plate 60 out of the storage chamber 39 until the pressure plate start 58 abuts a stop 51 of the plate clamping and tensioning device 53. A position detector 59 for the installation of the printing plate (27; 60) on the stop 51 gives a "good" signal to a control computer 66, whereupon the clamping flap 56 is closed. The start of the pressure plate 58 is clamped. The plate cylinder 3 is now rotated counterclockwise (forward) while the pressure roller 26 presses the pressure plate 60 against the plate cylinder 3. If the position detector 59 signals that the printing plate 60 is not in good contact with the stop 51 of the plate clamping device 54, the printing plate clamping process is terminated and an interference signal is generated.

When a plate cylinder position (printing plate clamping position) C (FIG. 3) is reached, in which the printing plate end 57 is pressed onto the clamping surface 63 by the pressure roller 26, the clamping flap 55 closes and clamps the printing plate end 57 firmly. Subsequent activation of the clamping elements clamps the pressure plate 60 on the plate cylinder 3.

The position C is subdivided into angular degrees only slightly (approx. 5 ° - 10 °) behind the disposal position A, i.e. H. the plate cylinder 3 only has to be rotated a little bit counterclockwise from the disposal position A until it reaches position C (FIG. 3).

In position C, the pressure roller 26 has slightly bent the pressure plate end 57 around an edge 61 of the plate cylinder pit 52, so that the pressure plate end 57 comes to lie within the periphery 62 of the plate cylinder 3 on the clamping support 63 of the clamping device 54 before it comes off the clamping flap 55 is held.

The pressure roller 26 is then pivoted back into the printing press operating position in that the double-acting working cylinder 19 pressurizes the piston rod 21, and the pressure roller 26 swivels about the axis 30 of the drive roller 29 from the plate cylinder 3.

The control computer 66 is connected to a number of solenoid valves 67 which, in the event of a command, switch or supply printing plate in the correct sequence depending on the positions of the plate cylinder 3 and in conjunction with suitable software and supply the actuating cylinders with working medium from a pressure source 72.

The positions A, B, C of the plate cylinder 3 are determined by means of an angle encoder 71 and fed to the control computer 66 (FIG. 4).

All electrical drives (e.g. plate cylinder drive M, drive for the transport roller 33) are also controlled by means of the control computer 66.

6 shows the diagram of a flow chart according to which the control computer 66 works in conjunction with counters and other position indicators (e.g. rotary pulse encoder 71) so that the printing plate 60 is automatically fed to the plate cylinder 3.

By actuating a start trigger 101, a query 102 of the safety conditions (for example, is the cover plate 11 closed?) Is carried out. Appropriate sensors are then activated. Not all If safety conditions are met, an interference signal 103 is generated.

A start warning signal 104 is given when all safety conditions are met. A renewed actuation of the start trigger 101 activates a drive of the plate cylinder 3 and rotates it into the plate cylinder position B (printing plate feed position) 106. When the plate cylinder position B is reached, the drive stops.

A subsequent query 107 relates to the presence of a new printing plate 60 in the printing plate feed or discharge device 9. Sensors provided but not shown to signal that the new printing plate 60 is missing, an interference signal 108 is generated. In a step 109, the clamping flap 56 is opened, the pressure roller 26 is placed against the plate cylinder 3, and the drive for all transport rollers 26, 29, 33 is activated.

The position detector 59 is then queried in a step 111. If the position of the pressure plate 60 on the stops 51 is incorrect, a further feed 112 of the pressure plate takes place. After three negative decisions 113, the transport rollers 26, 29, 33 are driven in reverse so that the printing plate 60 is transported back into the storage chamber 39; an interference signal 114 is also generated.

If the pressure plate 60 is correctly positioned, the drive for the transport rollers 26, 29, 33 is switched off in a step 116. The clamping flap 56 is then closed in step 117 and the pressure roller 33 of in step 118 the drive roller 29 turned off.

An activation 119 of the plate cylinder drive rotates the plate cylinder 3 forward into the plate cylinder position A. When the position is reached, the clamping flap 55 is opened in a step 121 and the plate clamping device 54 is moved to zero.

In step 122, the plate cylinder 3 is moved into the plate cylinder position C. The plate cylinder 3 is not stopped between positions A and C.

When the plate cylinder position C is reached, the clamping flap 55 is closed in a step 123 and then the plate clamping device 54 is activated. Then an end 124 signal is generated.

FIG. 7 shows the flowchart for releasing and removing the printing plate 27 from the plate cylinder 3 or pushing it into the printing plate memory 9.

By actuating a start trigger 201, a query 202 of the safety conditions (e.g. is the cover plate 11 closed?) Is carried out. Appropriate sensors are then activated. Among other things, there is also a query as to whether the printing plate memory 9 is free. If these conditions are not met, an interference signal 203 is generated. If all safety conditions are met, a start-up warning signal 104 is generated.

By actuating the start trigger 201 again, the plate cylinder 3 is rotated into the plate cylinder position A in step 205. Upon reaching the Plate cylinder position A, the pressure roller 26 is placed against the plate cylinder 3 in a step 206. The pressure roller 33 is turned off by the drive roller 29. The ejection fingers 45 are activated and plunge into the periphery 62 of the plate cylinder 3. The plate tension is turned off, the clamping flap 55 is opened.

Then, in a step 207, a drive 31, 32 for the transport rollers 26, 29 is activated. At the same time, the drive for the plate cylinder 3 is activated in step 208, so that it rotates backwards.

In step 209, after a plate cylinder rotation of approximately 50 mm in radians from plate cylinder position A, ejection fingers 45 are pivoted out of periphery 62 of plate cylinder 3.

In a subsequent step 211, after a plate cylinder rotation of approximately 150 mm in radians from plate cylinder position A, the pressure roller 33 is placed against the drive roller 29.

In step 212, the plate cylinder 3 moves into the plate cylinder position B. The clamping flap 56 is opened in the subsequent step 213.

In step 214, the pressure roller 29 is turned off.

In the last step 216, the drive 31, 32 for the transport rollers 29, 33 is issued after a transport path of approximately 150 mm in radians, starting from the plate cylinder position B.

Parts list

1

 Printing unit

2nd

 -

3rd

 Plate cylinder

4th

 Blanket cylinder

5

 -

6

 Impression cylinder

7

 -

8th

 Access page

9

 Printing plate feed or discharge device

10th

 -

11

 Cover plate

12

 -

13

 -

14

 Joint (upper)

15

 -

16

 Joint (lower)

17th

 Swingarm

18th

 Swingarm

19th

 Working cylinder

20th

 -

21

 Piston rod

22

 lever

23

 -

24th

 -

25th

 -

26

 Pressure roller

27th

 printing plate

28

 -

29

 Drive roller

30th

axis

31

 Sprocket

32

 Drive chain

33

 Pressure roller

34

 lever

35

 -

36

 joint

37

 Piston rod

38

 Housing (9)

39

 Storage chamber

40

 Working cylinder

41

 opening

42

 hinge

43

 Front wall (38)

44

 Breakthroughs

45

 Ejection finger

46

 Rear wall (38)

47

 Ejection finger wave

48

 Piston rod

49

 Working cylinder

50

 lever

51

 attack

52

 Pit (3)

53

 Plate clamping and tensioning device

54

 Plate clamping and tensioning device

55

 Clamp flap

56

 Clamp flap

57

 Pressure plate end

58

 Printing plate start

59

 Location detectors

60

Pressure plate (new)

61

 Edge (52)

62

 Periphery (3)

63

 Clamping pad (54)

64

 Breakthroughs

65

 Recess (54)

66

 Tax calculator

67

 Solenoid valve

68

 Lace (45)

69

 -

70

 -

71

 Angle of rotation encoder

72

 Pressure source

101)

. )

. )

 Follow-up steps to the schedule

. )

 "Printing plate feed"

124)

201)

. )

. )

 Follow-up steps to the schedule

. )

 "Printing plate removal"

216)

A

 Pressure plate release position

B

 Printing plate feed position

C.

 Pressure plate clamping position

Claims (14)

Method for automatically feeding a printing plate (27; 60) to a plate cylinder (3) of a rotary printing press, which i.a. Means (53, 54) for clamping and tensioning the pressure plate (27; 60), characterized in that the pressure plate (27; 60) is placed in a storage chamber (39) of a pressure plate feed or discharge device (9) in that the plate cylinder (3) is rotated into a pressure plate feed position (B), that the pressure plate (27; 60) by means of a number of transport rollers (29, 33) a clamping device (53, 56) of the plate cylinder (3) and by means of a pressure roller (26) a clamping device (54, 55) is supplied. Method for the automatic removal of a printing plate (27; 60) from a plate cylinder (3) of a rotary printing press, which has, inter alia, means (53, 54) for relaxing and releasing the printing plate (27; 60), characterized in that the plate cylinder (3) is rotated forward into a printing plate release position (A), that a clamping flap (55) is opened for the detection of a printing plate end (57), that the plate cylinder (3) is rotated backwards into a printing plate supply position (B), that a clamping flap (56) for detection a printing plate start (58) is opened so that the printing plate (27; 60) is fed to a storage chamber (39) of a printing plate feed or discharge device (9) by means of a number of transport rollers (29, 33). A method according to claim 1, characterized in that when the pressure plate (27; 60) rests against a stop (51) of the clamping device (53, 54), a "good" signal is generated by a system detection (59), which then causes the clamping flap (56) is closed. Device for feeding or discharging a printing plate (27; 60) to or from a plate cylinder (3) of a rotary printing press, which has means (53, 54) for automatically clamping and tensioning or relaxing and releasing the printing plate (27; 60) , characterized in that a printing plate feed or discharge device (9) is provided in that it has a number of transport rollers (29, 33), at least one of which can be driven. Device according to claim 4, characterized in that the pressure roller (33) is arranged so as to be adjustable against the drive roller (29). Device according to claims 4 and 5, characterized in that computer-controlled adjusting means (37, 40, 67) are provided for generating a positioning movement of the pressure roller (33). Device according to claims 5 to 7, characterized in that a pivotable pressure roller (26) is provided. Device according to claim 7, characterized in that adjusting means (19, 21, 67) are provided for producing a pivoting movement of the pressure roller (26). Device according to claim 4, characterized in that ejection fingers (45) are provided. Device according to claims 4 and 9, characterized in that the ejection fingers (45) are fastened on a pivotably mounted ejection finger shaft (47). Device according to claims 4, 9 and 10, characterized in that the ejection fingers (45) have tips (68), that the tips (68) are arranged so as to be pivotable into the periphery (62) of the plate cylinder (3). Device according to claims 4, 9 to 11, characterized in that openings (64) are provided in a clamping flap (55) of the plate clamping and tensioning device (54) and recesses (65) are provided in the plate clamping and tensioning device (54). Device according to claims 4, 9 to 12, characterized in that adjusting means (48, 49, 67) are provided for producing a swiveling movement of the ejection fingers (45). Device according to claim 4, characterized in that the storage chamber (39) of the printing plate feed or discharge device (9) is constructed in two parts and has a joint (42) connecting the two parts.

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